Paper webs or sheets, sometimes called tissue or paper tissue webs or sheets, find extensive use in modern society. Such items as paper towels, facial and toilet tissues are staple items of commerce. It has long been recognized that four important physical attributes of these products are their strength, their softness, their absorbency, including their absorbency for aqueous systems; and their lint resistance, including their lint resistance when wet. Research and development efforts have been directed to the improvement of each of these attributes without seriously affecting the others as well as to the improvement of two or three attributes simultaneously.
Strength is the ability of the product, and its constituent webs, to maintain physical integrity and to resist tearing, bursting, and shredding under use conditions, particularly when wet.
Softness is the tactile sensation perceived by the consumer as he/she holds a particular product, rubs it across his/her skin, or crumples it within his/her hand. This tactile sensation is provided by a combination of several physical properties. Important physical properties related to softness are generally considered by those skilled in the art to be the stiffness, the surface smoothness and lubricity of the paper web from which the product is made. Stiffness, in turn, is usually considered to be directly dependent on the dry tensile strength of the web and the stiffness of the fibers which make up the web.
Absorbency is the measure of the ability of a product, and its constituent webs, to absorb quantities of liquid, particularly aqueous solutions or dispersions. Overall absorbency as perceived by the consumer is generally considered to be a combination of the total quantity of liquid a given mass of tissue paper will absorb at saturation as well as the rate at which the mass absorbs the liquid.
Lint resistance is the ability of the fibrous product, and its constituent webs, to bind together under use conditions, including when wet. In other words, the higher the lint resistance is, the lower the propensity of the web to lint will be.
It is an objective of this invention to provide a soft, absorbent web material that is also strong both when wet and dry, and that has good lint resistance.